Practically speaking, human genealogies are systematic extensions of generations. Human families in all their diversity rest upon generations as do residential groups including nuclear and extended family households and villages. Inheritance of wealth, power, prestige and responsibility typically depends upon relations among generations, and a society's kinship terminology rests on generations but is a superstructure that may lie far above them.

Biological generations serve as the starting point for human systems of descent, marriage and kinship, but people go beyond the biological basics in creating ways to organize and operate their societies. In human societies, a generation is a “social construct” devised by people using human intellectual abilities, speaking human languages, elaborating and modifying human cultural traditions over many thousands of years. Human biological generations are just as “physical” as generations in all other life forms, but human familial generations are embedded in and are products of human cognition and cultures